20001755520 has 256 divisors, whose sum is σ = 73126656000. Its totient is φ = 5161605120.

The previous prime is 20001755513. The next prime is 20001755531. The reversal of 20001755520 is 2555710002.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 517011 + ... + 554349.

It is an arithmetic number, because the mean of its divisors is an integer number (285651000).

Almost surely, 2^20001755520 is an apocalyptic number.

20001755520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20001755520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36563328000).

20001755520 is an abundant number, since it is smaller than the sum of its proper divisors (53124900480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20001755520 is a wasteful number, since it uses less digits than its factorization.

20001755520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37398 (or 37380 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The spelling of 20001755520 in words is "twenty billion, one million, seven hundred fifty-five thousand, five hundred twenty".